论文标题
受到监测的量子动力学和基塔夫旋转液体
Monitored Quantum Dynamics and the Kitaev Spin Liquid
论文作者
论文摘要
带有局部投影测量值的量子电路动力学可以实现量子物质的纠缠状态丰富的范围。由Kitaev量子旋转液体的物理学动机[1]，我们研究（2+1）涉及局部投影测量的量子电路动力学，其中，受监测的轨迹认识到（i）具有拓扑量子顺序或（ii）“关键”相的阶段，其相对于面积的较大范围的“临界”阶段以及该阶段的阶段以及该阶段的阶段以及该阶段的阶段，该阶段与较长的范围范围的范围范围差异。对这些动力学的主要描述提供了对基塔夫蜂窝模型的Parton描述的不平衡概括，它允许对这两个阶段的通用特性进行分析理解，包括稳态的纠缠属性，系统在平衡方法和这些状态之间的方法中的动态。在拓扑排序的阶段中，可以在初始状态中编码两个逻辑Qubit，并在系统的线性维度上呈指数缩放的时间，而量子信息的鲁棒编码仍然存在于关键阶段。这些受监测动力学的广泛数值模拟证实了我们的分析预测。
Quantum circuit dynamics with local projective measurements can realize a rich spectrum of entangled states of quantum matter. Motivated by the physics of the Kitaev quantum spin liquid [1], we study quantum circuit dynamics in (2+1)-dimensions involving local projective measurements, in which the monitored trajectories realize (i) a phase with topological quantum order or (ii) a "critical" phase with a logarithmic violation of area-law-scaling of the entanglement entropy along with long range tripartite entanglement. A Majorana parton description of these dynamics, which provides an out-of-equilibrium generalization of the parton description of the Kitaev honeycomb model, permits an analytic understanding of the universal properties of these two phases, including the entanglement properties of the steady-state, the dynamics of the system on the approach to equilibrium, and the phase transition between these states. In the topologically-ordered phase, two logical qubits can be encoded in an initial state and protected for a time which scales exponentially in the linear dimension of the system, while no robust encoding of quantum information persists in the critical phase. Extensive numerical simulations of these monitored dynamics confirm our analytic predictions.
